Process of and apparatus for making longitudinally and laterally stretchable creped webs



Jan. 10, 1950 P. w. DORST 2,

PROCESS OF AND APPARATUS FOR MAKING LONGITUDINALLY AND LATERALLY STRETCHABLE CREPED wsss Filed July 29, 1946 Gui PINVENTOR ATTORNEYS.

Patented Jan. 10, 1950 PROCESS OF AND APPARATUS FOR MAK- lNG LONGITUDINALLY AND LATEBALLY STRETCHABLE CREPED WEBS Paul W. Dorst, Cincinnati, Ohio, assignor to Cincinnati Industries, Inc., Lockland, Ohio, a corporation of Ohio Application July 29,1946, Serial No. 686,899

17 Claims.

My invention relates to the creping of webs in such fashion as to produce diagonal creping crinkles therein, or crossing sets of diagonal creping crinkles or contractions.

The operation of creping, as is well-known, comprises causing a web (which may be of paper, cloth or other material) to adhere to a creping surface from which it is removed by a doctor or blade. Usually the web is caused to adhere to the surface of a. rotating cylinder, turning against a stationary doctor. A positive creping adhesive is preferably used, although in some instances a wetted web will cling sufficiently to the surface of a creping cylinder. The angle formed by the leading edge of the doctor and the tangent to the cylinder at the like of contact of the doctor with it is known as the "creping V, and largely determines the nature of the crepes produced and the degree of stretchability imparted to the web by the creping operation.

Hitherto, in the production of universally stretchable creped webs, it has been the commercial practice to cause them to adhere to the surface of a cylinder, and to dispose the knife or doctor in such a way that its leading edge is diagonal to the direction of motion of the web as it approaches the doctor. Hence, the leading edge of the doctor follows a substantially helical line on the surface of the cylinder. Because of the difliculty of providing and maintaining a suitable creping V all along the working edge of a rigid, planar knife which is cut out so that its edge will conform to the surface of a cylinder along a substantially helical line, it is usual to provide a flexible knife or doctor which is, as it were, wrapped about a portion of the surface of the cylinder and is supported in an inclined position. The diagonal creped web is led away from the knife in upside down position and in a direction substantially axially of the cylinder. This means that the web leaves the cylinder in a transversely curved condition. It is usual to make the diameter of the cylinder very large; but, even so, difficulty is encountered in maintaining the same degree of contraction all along the working edge of the doctor.

In the making of universally stretchable webs, it is further the usual practice to produce a set of diagonal creping crinkles or contractions in the way just set forth, whereupon the web is recreped with the formation of a second set of creping crinkles or contractions in the opposite diagonal direction.

The principal object of my invention is the provision of means and a method for producing a diagonal set of creping crinkles or contractions, or crossing sets thereof, in such fashion as to avoid the difliculties encountered with previous procedures and apparatus. It is my object to provide a creping operation for which the apparatus is simpler and less expensive, taking up also less factory space. It is an object of my invention to provide a means and method in which the degree of stretchability imparted to the web can be more accurately controlled and can be made more uniform along the working face of the doctor.

These principal objects, and others which will be set forth hereinafter or will be apparent to one skilled in the art upon reading these specifications, I accomplish by that procedure and in that apparatus of which I shall now describe exemplary embodiments. Reference is made to the drawings which form a part hereof, and in which:

Figure l is a diagrammatic end elevation of a simple form of my apparatus.

Figure 2 is a side elevational view thereof.

Figure 3 is a partial cross-sectional view showing the relationship of the doctor to the surface of a creping cylinder, and means for supporting the doctor in its working position.

Figure 4 is a plan view of apparatus for pro ducing crossing sets of creping crinkles or contractions.

Figure L5 is a diagrammatic perspective of apparatus in which two creping operations may be carried on on the creping cylinder.

Figure 6 is a vertical cross-section taken along the line 8, 6 of Figure 5.

The basis of the invention is my discovery that, if a web is adhered to a creping surface and is moved relatively to a transverse creping doctor, and, if the doctor is simultaneously moved in the direction of the extent of its working edge, the web will be contracted or crinkled, but at the same time will be progressively displaced laterally in such fashion that it tends to oil at an angle. This angle can be varied by varying the relative speeds of the knife or doctor and the web. If the width of the creped web be measured in a direction perpendicularly to its side edges it will be found to have been contracted width-wise, and further any creping crinkles formed therein will now be found to lie diagonally of the axis of the web.

Reference is made first to Figure 4. Here a web I is shown as being led to a. creping cylinder 2 to the surface of which it is caused to adhere in any suitable fashion. As it passes about the surface of the cylinder it encounters a creping knife or doctor 3 which removes it from the surface of the cylinder and crepes or contracts it. The web as it approaches the cylinder is moving in the direction indicated by the arrow 4 and has a width W.

Now, if the doctor 3 is caused to move continuously in the direction of the arrow 5, the web will be displaced as aforesaid and will leave the doctor and cylinder in an angular direction indicated by the arrow 7. If its width is now measured in a direction perpendicular to its side edges, it will be found to have a new and lesser width W1. A shading in Figure 4 represents generally the direction of creping crinkles formed in the web, and it will be seen that these creping crinkles lie aslant to the lateral axis W1 of the web.

In a continuation of the process the already creped web may be led and caused to adhere to the surface of a second creping cylinder I from which it is removed by a knife or doctor 9. If

port I. on the frame of the machine. The bracket bears pivoted roller means I] contacting the upper edge of the band, and upper and lower pivoted roller means I 8 and i8 contacting the side faces of the band. In this fashion the band is held against the cylinder so as to act as a creping knife. Its lower lateral edge forms the creping V with the tangent to the cylinder at the creping line; and this creping v may be varied both by changing the tilt of the knife and by suitably conflguring the knife edge. I have shown the sheaves II and H in a tilted position in Figures l and 2. This is usually advantageous for this knife or doctor is continuously moved in the direction of the arrow Hi, the web will tend to leave the creping cylinder and doctor in a direction I l aslant to the direction I. It will be found to have a new and still smaller width W: and to have been provided with crossing sets of slantwise creping crinkles or contractions, as again diagrammatically illustrated by shading.

If the degrees of stretchability imparted by the doctors 3 and 9 are equal, direction II will be parallel to direction 4. But, as indicated above, the degree of stretchability imparted by one of my creping operations will be dependent upon the relative speeds of travel of the web and the doctor and hence can be adjusted over a very wide range.

- In practicing my invention I am not limited to the use of creping cylinders, but may employ other creping surfaces such, for example, as that of a continuous traveling band. Nor is it a limitation on my invention that the working edge of the knife or doctor be set at an angle of 90 to the longitudinal axis of the web. However, it is one of the advantages of my process that a creping cylinder may be employed which is relatively small in diameter, together with a knife which contacts the surface of the cylinder along a line substantially parallel to its axis. Since the knife or doctoris to be caused to move continuously in one direction throughout a creping operation, I

prefer to provide it in the form of an endless band of flexible and sufficiently strong substance. A doctor in the formof a steel band somewhat similar toa band saw without teeth is excellent for my purpose.

Figures 1 and 2, I have shown the web I approaching the cylinder 2 in the direction 4 and being pressed against the surface of the cylinder by a suitable pressure roll l2. The doctor I is in the form of an endless steel band passing over sheaves or rollers l3 and M so that one flight of the knife brings its edge against the surface of the cylinder along a line substantially parallel with the axis. of the cylinder. In the apparatus diagrammatically illustrated herein, the cylinder 2 will be driven under power as will likewise one or both of the sheaves l3 and I4.

If the band is to act satisfactorily as a creping doctor, its working edge must be held against the surface of the cylinder throughout its working length. It is of advantage to tilt the band against the surface of the cylinder and to support it at intervals throughout its working flight. This is illustrated in Figure 3 where I have shown a bracket means I! adjustably attached to a supobtaining a tilted position of the band; but the sheaves l3 and I4 may, if desired, lie in a plane radial to the cylinder and the working flight of the knife may be tilted solely by bracket means such as are illustrated in Figure 3.

It is most advantageous in using my apparatus to remove the creped web la in a direction back upon itself as illustrated in the various figures. It could be carried up and over the knife, but if creped by means of a positive and adhesive subcoated surface.

stance this might involve supporting it from the Carried away in the manner shown with the coated surface uppermost is advantageous from the standpoint of web handling. In an apparatus where the working edge of the knife lies along a line substantially parallel to the axis of the creping cylinder, it will be observed that the web can be carried away in a flat condition at any desired angle to the tangent plane, and that the removal of the creped web from the creping apparatus does not involve an unequal stretching of the web in different parts. This is a great advantage of my procedure over those in present day commercial use.

The direction of displacement of the web is determined by the direction of movement of the knife or doctor; and in my machines I prefer to provide means whereby the doctor can be driven in either direction as desired. This enables me to produce crinkles or contractions in the web in either diagonal direction selectively.

Double creping may be done in successive operations on the same cylinder. For this purpose I change the direction of movement of the doctor between operations since, when a web is passed through the apparatus and rewound into a roll, the web will have been reversed end for end when the roll is brought back to the entering side of the apparatus for re-creping, but the effective direction of the original crinkles will not have changed. Hence, to produce a set of crinkles in the opposite diagonal direction, I reverse the movement of the knife as indicated.

In a continuous double creping apparatus such as is diagrammatically illustrated in Figure 4, the

degree of stretchability imparted to the web in the separate creping stages will determine the angularity of the directions 1 and l I to the direction I. The working elements of the apparatus may be made adjustable, if desired, as to position, to accept webs traveling in different directions, when changes in resident stretchability are desired, or the direction of the web may be altered by handling means to suit a fixed position of the working elements.

It will be seen from the above that my creping procedures have applicable to them all of the features of control hitherto developed for other creping operations, with or without positive adhesive substance. I

As illustrated in Figures 5 and 6 I may employ 75 a single band to provide two effective creping doctors against a single cylinder whereby two creping operations may be carried on at the same time. Here I have shown a creping cylinder with a band 2| passing over sheaves 12, 23, 24, and 26 in such a way as to have an upper flight 2ia adjacent one portion of the cylinder surface and a lower flight Zlb'adjacent another portion of the cylinder surface. Two webs may be brought against different parts of the surface of cylinder 20 and simultaneously creped in accordance with my process. This type of apparatus will normally be used for the simultaneous creping of separate webs. To attempt simultaneously to crepe different parts of the same web would involve the provision of taking up and paying out apparatus to compensate for the contraction of the web at the first stage.

As compared with current apparatus and procedures for making diagonally creped or contracted webs, it will be seen that my procedure and apparatus offer certain important advantages. No complicated curves or shapes are required for a doctor or its holding means. The creping drum or drums may be quite small in diameter. An advantage singular to my invention is that my knife or doctor may be cleaned continually while in operation to prevent the accumulation of adhesive on the machine, as indicated generally at 26 in Figure 5. Such accumulation of-adhesive would result eventually in the release of adhesive lumps to the web. The angularity of the creping and hence the degree of lateral stretchability imparted to the contracted web may be varied as desired by the simple expedient of varying the speed of the knife relative to that of the creping drum or cylinder. Hitherto the degree of control which could be exercised by varying the speed of the drum was small, and real changes in the angularity of the crepes had to be sought in changes of the position of the doctor, which were hard to effect.

Similarly in my machine changes in the angularity of the creping V may be eifected simply and rapidly by tilting the knife more or less as desired. Because the knife in my preferred embodiment follows a straight path, the bracket means [5 and/or the support means it may be arranged for adjustability, and adjustment may .be effected even while the machine is in operation.

Again, both the creping drum and the knife are disposed in my apparatus so as to prevent deep scoring of the drum. My knife may be changed quickly when necessary. In order to maintain the same creping V all across the face of the web, it is not necessary to grind the knife edge to different angularity in different parts. On the contrary, in the preferred form of my apparatus the angularity of the knife edge can be constant throughout the length of the band. My knife may be reground with simple equipment, and it is quite possible to regrind it while in position on the machine.

It will be understood that the teachings made hereinabove may be incorporated in apparatus of various kinds, and that modifications may be made in my invention without departing from the spirit of it.

Having described my invention in certain exemplary embodiments what I claim as new and desire to secure by Letters Patent is:

1. A process of creping webs which comprises causing a web to cling to a creping surface, producing relative motion of said creping surface and a creping doctor whereby to cause said doctor to remove said web from said creping surface in a contracted condition, and simultaneously moving said doctor in a direction transverse the movement of said web whereby to displace said web and cause it to leave the creping line of said surface and doctor in a diagonal direction, so as to produce a web, in effect, contracted widthwise and in which the contractions lie aslant to the axis of the contracted web.

2. A process of contracting a web which comprises causing said web to cling to a creping surface, producing relative motion of said creping surface and a doctor in the direction of the longitudinal axis of said web, whereby to cause said doctor to remove said web from said creping surface and contract it, and simultaneously producing movement of said doctor relative to said creping surface continuously in a direction transverse the longitudinal axis of said web, whereby to displace said web progressively in said direction as it is being contracted.

3. A process of contracting a web which comprises causing said web to cling to a creping surface, producing relative motion of said creping surface and a doctor in the direction of the longitudinal axis of said web, whereby to cause said doctor to remove said web from said creping surface and contract it, and simultaneously producing movement of said doctor relative to said creping surface continuously in a direction transverse the longitudinal axis of said web whereby to displace said web progressively in said direction as it is being contracted, and carrying said web away from said doctor in upside down position and in a direction at an angle to its first direction of travel, the said angle being determined in part at least by the speed of said last mentioned relative movement of said doctor and said creping surface.

4. A process of contracting a web which comprises causing said web to cling to a creping surface, producing relative motion of said creping surface and a doctor in the direction of the longitudinal axis of said web, whereby to cause said doctor to remove said web from said creping surface and contract it, and simultaneously producing movement of said doctor relative to said creping surface continuously in a direction transverse the longitudinal axis of said web whereby to displace said web progressively in said direction as it is being contracted, and thereafter again causing said web to cling to a creping surface, producing relative movement of said creping surface and a doctor, whereby to remove said web from said creping surface and contract it,

and continuously producing relative movement of said doctor and said creping surface in a direction transverse the longitudinal axis of the contracted web, whereby to produce in said web crossing sets of contractions.

5. A process of contracting a web which comprises causing said web to cling to a creping surface, producing relative motion of said creping surface and a doctor in the direction of the longitudinal axis of said web, whereby to cause said doctor to remove said web from said creping surface and contract it, and simultaneously producing movement of said doctor relative to said creping surface continuously in a direction transverse the longitudinal axis of said web whereby to displace said web progressively in said aace'ss l i 7 web from said creping surface and contract it, and continuously producing relative movement of said doctor and said creping surface in a direction transverse the longitudinal axis of the contracted web, whereby to produce in said web crowing sets of contractions, and in each creping operation carrying the web away from the creping line in an upside down position and at an angle to its direction of motion in approaching the creping line.

6. In creping apparatus. means providing a creping surface and a doctor having an edge contacting with said creping surface. means for providing continuous relative motion of said crepe ing surface and doctor in a creping direction and means for providing relative motion of said doctor and creping surface in a direction transverse the first mentioned direction.

7. In creping apparatus means providing a creping surface, a creping doctor, means for moving said creping surface against said doctor in one direction, and means for continuously moving said doctor in a direction transverse said first mentioned direction.

8. Apparatus as claimed in claim 7 wherein said means providing said creping surface is a cylinder and wherein said-doctor is in the form of an endless band.

9. In creping apparatus a creping cylinder, a doctor in the form of an endless band, rotative means mounting said doctor for movement in a path having a portion substantially parallel with the axis of said cylinder so that an edge of said band may be brought against the surface of said cylinder, means for driving said cylinder and means for driving said band.

10. In creping apparatus a creping cylinder, a

doctor in the form of an endless band, rotative means mounting'said doctor for movement in a path having a portion substantially parallel with the axis of said cylinder so that an edge of said band may be brought against the surface of said cylinder, means for driving said cylinder, means for drivin said band, and further means for tilting said band so as to bring an edge thereof against said cylinder with said band tilted out of a tangential plane.

11. In creping apparatus a creping cylinder. a doctor in the form of an endless band, rotative means mounting said doctor for movement in a path having a portion substantially parallel with the axis of said cylinder so that an edge of said band may be brought against the surface of said cylinder, means for drivingsaid cylinder, means for driving said band, and further means for tilting said band so as to bring an edge thereof against said cylinder with said band tilted out of a tangential-plane, said last mentioned means comprising rollers contacting an edge and two faces of said band whereby to mount said band for motion while maintaining it in a tilted position against said-cylinder.

12. In creping apparatus a creping cylinder,

a. creping knife in the form of an endless band,

means for bringing a portion of said band with its edge in contact with said cylinder along a .tor in the form of an with the tangent plane of 8 line substantially parallel to the axis of said cylinder, means for continuously driving said cylinder and means for continuously driving said band.

13. In creping apparatus a creping surface, a creping doctor or knife in the form of an endless closed band, means for supporting a portion of said band in creping position so as to form a creping line with a creping surface, and means for driving said band in the direction of its length so as to move said creping line.

14. In creping apparatus a crepin surface, a creping doctor or knife in the form of an endless closed band, means for supporting a portion of said band in creplngposition so as to form a creping line with a sin-face, means for driving said band in the direction of its length so as to move said doctor along said creping line, and means for continuousl cleaning said doctor, said means with it at a position other line.

15. In creping apparatus, a creping cylinder, means for driving said creping cylinder, a crepingdoctorintheformofanendlessbandmeans for mounting said band for movement in elongatedpathsoneofsaidpathslyin'goneach side of said cylinder, and means for bringing said bandineachofsaidpathsinatilted sition against the cylinder surface.

16. In creping apparatus, a creping drum, a knifeintheformofanendleasbandmeans mounting said knife for longitudinal movement, means bringing a portion of said knife against the surface of said cylinder so that it may act as'a creping doctor, a second creping cylinder, 9. second knife in the form of an endless band with mounting means aforesaid, said second cylinder being located with its axis at an angle to cylinder, means for driving said cylinders, and means for driving said knives in effectively opposite directions.

17. In creping apparatus a creping cylinder, means for driving said cylinder, 8 creping docendless band, means mounting said doctor for movement as a band means for tilting a portion of said doctor into edgewise contact with the surface of said cylinder along a line substan ially parallel with the axis of said cylinder, means for driving said doctor, and means for v rying the angularity of said'tilting means so as to vary the mgularity of a creping V formed by the edge of said doctor said creping ylinder. PAUL W. DORST.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,782,767 Rowe Nov. .25, 1930 2,008,182 Kemp July 10, 1935 2,300,908 Broughton Nov. 3, 1942 doetoralongsaid' thanapositioninsaidcreping 

